Pressed trim button, entire eletrical system died

kd7isf

Petty Officer 2nd Class
Joined
Aug 20, 2004
Messages
162
Hi,

OK, here we go with another weird one. Still tinkering with my friends merc 3.0 was running it on the hose today and pressed the button to lift the drive up a little bit so I could spin the wheel back and forth...

Well, when I did that, the engine died and the dash went dark.... :confused:
Also lost power to the trim...

I went down near the starter and wiggled wires.. When I wiggled the power wire for the trim, everything came back on... Wiggled it again, everything went back off...

Looking at the wiring diagram, that wire ONLY powers the trim -- nothing else -- why am I losing dash/ignition power when i wiggle this wire? Makes no sense....

Any ideas?

Thanks!!!
 

26aftcab454

Lieutenant Commander
Joined
May 12, 2009
Messages
1,510
Re: Pressed trim button, entire eletrical system died

bad connection to battery.
 

Bondo

Moderator
Staff member
Joined
Apr 17, 2002
Messages
71,090
Re: Pressed trim button, entire eletrical system died

Hi,

OK, here we go with another weird one. Still tinkering with my friends merc 3.0 was running it on the hose today and pressed the button to lift the drive up a little bit so I could spin the wheel back and forth...

Well, when I did that, the engine died and the dash went dark.... :confused:
Also lost power to the trim...

I went down near the starter and wiggled wires.. When I wiggled the power wire for the trim, everything came back on... Wiggled it again, everything went back off...

Looking at the wiring diagram, that wire ONLY powers the trim -- nothing else -- why am I losing dash/ignition power when i wiggle this wire? Makes no sense....

Any ideas?

Thanks!!!

Ayuh,... I'm guessin' you've got a really Bad ground connection...
 

tpenfield

Moderator
Staff member
Joined
Jul 18, 2011
Messages
18,147
Re: Pressed trim button, entire eletrical system died

KD7-

Definitely a weird one as you say . . . my guess would be something going crazy at the main circuit breaker . . . like bad connection or the breaker is becoming faulty.
 

ENSIGN

Lieutenant Junior Grade
Joined
Jun 21, 2009
Messages
1,179
Re: Pressed trim button, entire eletrical system died

Disconnect the battery and remove and clean all connections on the starter motor terminals.Also remove and clean all the ground wires going to the engine block.
 

kd7isf

Petty Officer 2nd Class
Joined
Aug 20, 2004
Messages
162
Re: Pressed trim button, entire eletrical system died

ok, got it.. LOTS of corrosion on the battery cables at the starter... removed corrosion and tightened nut -- problem solved, new problem created............. :facepalm:

Now the alternator charges the battey to 16 volts.... Anyone know where the regulator is? This one has the two small wires (field wires) coming from somewhere past the back of the engine...

Thanks!!!
 

ENSIGN

Lieutenant Junior Grade
Joined
Jun 21, 2009
Messages
1,179
Re: Pressed trim button, entire eletrical system died

The regulator is built into the alternator.Check the charging voltage AT THE BATTERY with a voltmeter. It should be 13.8 to 14.2 volts
 

fat fanny

Lieutenant Commander
Joined
Feb 9, 2006
Messages
1,935
Re: Pressed trim button, entire eletrical system died

I would suggest disconnecting the battery and going through the whole witing harness cleaning and lubing verey connection then re-attaching them securly. You still must have a groung issue somewhere! Good luck!!!!
 

pyrotek

Petty Officer 2nd Class
Joined
Nov 19, 2011
Messages
183
Re: Pressed trim button, entire eletrical system died

i don't think a grounding issue is going to give you 16V. Sounds more like the regulator to me.

You might want to add some dielectric grease to that starter connection to avoid future corrosion.
 
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